This invention relates to cellular resin foam materials which are resistant to the passage of noxious undesirable chemicals in the form of liquids, condensible vapour and gases, but which are relatively permeable to air and water vapour. More particularly, the invention relates to the fire-proofing of such materials.
For protection against noxious chemicals such as the gases and smokes employed in chemical warfare, and also against dangerous chemicals such as industrial poisons and pesticides which are generally in the form of sprays or mists, it is customary to use protective equipment and in particular protective clothing which incorporates a gas and vapour adsorbent material.
The prerequisites of an ideal gas-proofed material, in particular for use as wearing apparel, are as follows. The material should be such that it adsorbs a relatively large portion of noxious chemicals such as chemical warfare agents while retaining permeability to oxygen or air; the supporting material for the adsorbent should be substantially porous in order to permit perspiration or other liquids to evaporate from the wearer's body; the material comprising the support should substantially retain its flexibility after being combined with the gas adsorbent; and the gas adsorbent should be substantially permanently bound to the supporting material in order to prevent the adsorbent from becoming dislodged from the support by rain, laundering or rough usage or by the softening effect of moisture and perspiration. Finally the gas-proofed material should be capable of reuse after decontamination.